Zoonotic and emerging infectious diseases represent an increasing and very real threat to global health, and it is essential that we expand our understanding of the pathogenesis and prevention of these diseases because of the increasing density of human populations, the increased exposure to domestic animal populations, and the crowding of wildlife into limited areas with frequent livestock and human contact. To address the growing need for infectious disease research, a COBRE Center of Excellence was established at Montana State University (MSU), with the goal of positioning Montana as a national leader in research on zoonotic infectious diseases. Over the past 9 years, the Center has been extremely successful, resulting in infrastructure development (facilities and equipment), recruitment and support of junior investigators (7 COBRE Projects, 6 new hires, and 20 Pilot Projects), and formation of a cohesive Center of investigators. The synergism of these components has resulted in the establishment of a solid foundation for infectious disease research in the region. Importantly, these efforts have fostered faculty career development and have created a pipeline of new researchers with interest and expertise in infectious disease pathogenesis. An essential component of our Center of Excellence is a state-of-the-art Cellular Analysis Core (Core B). This Core provides service, consulting, mentoring, and training in flow cytometry, confocal microscopy, and histology. Previous COBRE l/ll funding, combined with an investment in new equipment of neariy $900,000 specifically for flow cytometry and >$1.6 million in all Core B components combined over the past nine years has allowed us to establish facilities that are unrivaled in the university, state, and region. The Cellular Analysis Core was integral to the success of neariy all COBRE-funded projects, as well as an incredible asset for the university, in general. This Core serves as the cornerstone for the Center now and into the future, beyond COBRE III. The primary objectives in COBRE III will be to continue to expand the capabilities and use of the Cell Analysis Core, and position it for long-term sustainability. Four specific Aims will be pursued to address these objectives: Specific Aim 1: To provide and maintain state-of-the-art instrumentation for use in qualitative and quantitative cell analysis in support of COBRE funded Pilot Grant projects. Center research programs, and other MSU research programs; Specific Aim 2: To provide instruction and mentoring per the capabilities of the Cellular Analysis Core; Specific Aim 3: To provide service and consulting in flow cytometry, confocal microscopy, and histology; and Specific Aim 4: To pursue ongoing assessment of the effectiveness of the Cellular Analysis Core. The Cellular Analysis Core will continue to be highly interactive and collaborative, and will play an important role in expanding the infectious disease research enterprise in Montana.